ambrosia

In Greek mythology, the food of the gods, as nectar was their drink (from
the Greek ambrotes, "immortal"). It gave to those who ate it immortal
youth and beauty. It was brought by doves to Jupiter, and was occasionally
bestowed upon such human beings as were the peculiar favorites of the gods.
Ambrosia was also used as a fragrant salve, which the goddesses employed
to heighten their beauty; with which Jupiter himself anointed his locks;
and which had the property of preserving bodies from decay.

The term was applied by Pliny, and by early herbalists, to various plants.
Hindu mythology has also its amrita, the beverage of the gods;
and the gods of the Scandinavian pantheon were preserved in perpetual vigor
by eating the apples guarded by Idun.